1. Field of the Invention
This invention relates to a rapid process for imparting water repellancy to fibrous cellulosic textile materials and more particularly to a process wherein cellulosic textile materials are acylated with an isopropenyl ester and then heat cured in an acid catalyzed reaction.
2. Description of the Prior Art
Acylation of cellulosic textile materials such as cotton is known in the art. Acylation of cotton has been achieved principally by the following methods of esterification: (a) reaction with an acid chloride in dimethyl formamide solvent (Textile Res. J. 35, 365-376, 1965); (b) treatment with a benzene solution of the fatty acid and trifluoroacetic acid anhydride (Textile Res. J. 37, 706-7, 1967); (c) the Karrar method in which the cotton is first padded with aqueous sodium hydroxide and is then immersed in a carbon tetrachloride solution of an acid chloride (U.S. Pat. No. 1,897,026); and (d) reaction of dry sodium cellulosate with an acid chloride in dimethyl formamide. (JAOCS 48, 284-290, 1971). The effect of the nature and chain length of the fatty acid upon the physical properties of cotton cellulose is also known (Textile Res. J. 42, 161-167, 1972; Ibid., 34, 1102-1104, 1964; Ibid., 36, 828-837, 1966; Am. Dyestuff Reptr., 51, 428-430, 1962.)
The chemical reactions of enol esters, especially isopropenyl stearate, is also known (JAOCS, 48, 657-660, 1971; Ibid., 48, 373-375, 1971; Ibid., 45, 189-193, 1968; J. Org. Chem., 38, 174, 1973; Ibid., 29, 646-650, 1964; Ibid., 34, 2486-88, 1969; Ibid., 35, 2351-53, 1970; Ibid., 39, 3551-52, 1972).
Cellulosic textile materials have been esterified with sorbic acid and with unsaturated long chain fatty acids in the presence of trifluoroacetic acid (U.S. Pat. Nos. 3,617,201 and 3,493,319). Cotton has been partially esterified with long chain acid halides to make it resilient (U.S. Pat. No. 3,432,252).